《数字测图》课件-3.1.3碎部点的选取及跑镜方法认识

数字测图DigitalMappingTheSelectionandRunningMethodsofFragmentaryPointsareRecognized碎部点的选取及跑镜方法认识数字测图的实施过程本质就是通过采集野外碎部点的位置信息，碎部点的连接关系和由点构成的线、面图形的属性信息，仪器自动存储位置信息，草图记录连接关系和属性，仪器和草图记录的信息通过碎部点的点号进行关联，最终实现野外数据采集和内业成图相匹配。Theessenceofdigitalmappingimplementationistocollectthepositioninformation,connectionrelationship,andattributeinformationofthefragmentarypointsinthefield,andtoautomaticallystorethepositioninformationoftheinstruments,recordtheconnectionrelationshipandattributesofthesketch,andassociatetheinformationrecordedbytheinstrumentsandthesketchwiththepointnumberofthefragmentarypoints.Ultimately,thefielddatacollectionandthein-housemappingmatch.碎部点的选取及跑镜方法认识TheSelectionandRunningMethodsofFragmentaryPointsareRecognized野外数据采集对象FieldDataCollectionObject地物是人工修葺的构筑物或自然形成的地表上相对固定的物体，一般用图示符号来表示。Terrainareman-madestructuresornaturallyformedrelativelyfixedobjectsonthegroundsurface,whicharegenerallyrepresentedbygraphicalsymbols.野外数据采集对象FieldDataCollectionObject地貌是指地面高低起伏的变化形态，一般用等高线表示。Topography,whichreferstothechangingpatternsoftheground'supsanddowns,andisgenerallyrepresentedbycontourlines.野外数据采集对象FieldDataCollectionObject不论采集对象是哪一类，都是要通过碎部点来反映其位置、形状、大小、范围、面积和变化形态的，因此野外碎部点其本质就是用于体现地物和地貌的特征的关键位置点。However,nomatterwhichtypeofobjectiscollected,itslocation,shape,size,scope,areaandchangepatternarereflectedthroughfragmentationpoints,sotheessenceoffieldfragmentationpointsisthekeylocationpointsusedtoreflectthecharacteristicsofterrainandtopography.碎部点的选取SelectionFragmentPoints01地物观测Terrainobservation

碎部点的位置一般选择为地物的外围边界点、地物的中心点、地物走向发生变化的转折点，记录了碎部点的位置信息以及记录碎部点的连接关系和属性。Thelocationoffragmentarypointsisgenerallychosenastheboundarypoint,centerpoint,andturningpointofterrain,whereterraindirectionchanges.Itrecordsthelocationinformationoffragmentpoints,aswellastheconnectionrelationshipandattributesoffragmentpoints.碎部点的选取SelectionFragmentPoints02地貌观测Topographyobservation

碎部点一般选择为地形坡度发生变化的起点和终点位置，称为高程点，一般只记录高程点的位置信息，无需记录连接关系和属性。Thefragmentarypointisgenerallychosenasthestartingandendingpositionoftheslopechange,calledelevationpoint,andonlyrecordsthelocationinformationofelevationpoint,withouttheneedtorecordtheconnectionrelationshipandattributes.碎部点的选取SelectionFragmentPoints01在野外碎部点选取时，除了已经提到的对地物、地貌形态描述的特征点位置外，是实际实施过程中，碎部点的选取还与测图比例尺和基本等高距有直接关联。Whenselectingfieldfragmentarypoints,inadditiontothepositionofcharacteristicpointsfordescribingtheshapeofterrainandtopography,inpracticalimplementation,theselectionoffragmentarypointsisalsodirectlyrelatedtothesurveyratioandbasiccontourinterval.碎部点的基本要求BasicRequirementsofFragmentPoints01在测绘实施规范中明确规定，地物的选取需满足大于图上0.1mm的表示要求，这个要求即明确了地物碎部点的采集与测图比例尺有直接关系。Inthesurveyimplementationregulations,itisspecifythattheselectionofterrainmustmeettherequirementofmorethan0.1mmonthemap,whichclearlyspecifiesthatthecollectionofterrainfragmentarypointsisdirectlyrelatedtothesurveyratio.碎部点的基本要求BasicRequirementsofFragmentPoints02在地貌碎部点的采集时，地貌点的选取与测图基本等高距有直接关联，坡度变化或高差变化需大于基本等高距时进行地貌碎部点的采集。Whencollectingfragmentarypointsoftopography,theselectionoftopographypointsisdirectlyrelatedtothebasiccontourintervalofthesurvey.Slopechangeorheightchangethatisgreaterthanthebasiccontourintervalshouldbecollectedwhentopographyfragmentarypointsarecollected.碎部点的基本要求BasicRequirementsofFragmentPoints03在地貌平整或地物长距离无高差或方向变化的情况下，要求图上2㎝必须采集碎部点。Inthecaseofflattopographyorlongdistancebetweenterrainwithoutheightordirectionchanges,itisrequiredtocollectfragmentarypointsonthemapevery2cm.碎部点的采集FragmentaryPointCollection全站仪+棱镜或GNSSRTK移动站Totalstation+prismorGNSSRTKmobilestation碎部点的观测ObserveTopographyFragmentaryPoints在进行地貌碎部点观测时，选择的碎部点是高差变化大于基本等高距的变坡位置的高程点，碎部点的观测路线一般是沿着等高线的平行方向进行采集。Whenobservingtopographyfragmentarypoints,wechoosefragmentarypointswithaheightdifferencegreaterthanthebasiccontourintervalatthechangeofslopeposition.Theobservationrouteoffragmentarypointsisgenerallyalongtheparalleldirectionofcontourlines.把测区划分为若干个小范围的区域，再根据地物的不同属性来进行地物碎部点分类采集，或者在小范围内按照行走路线，经过什么测什么。Thesurveyareaisdividedintoanumberofsmallareas,andthenaccordingtothedifferentattributesoftheterrainoftheterraintocarryouttheclassificationofthecollectionofterrainfragmentationpoints,orinasmallareainaccordancewiththewalkingroute,throughwhattomeasurewhat.碎部点采集路线规划PlanningofCollectionRouteforFragmentPoints分类观测的优点是连接关系和属性记录简单，缺点是路线经常往返、重复。Theadvantageofclassificationobservationisthattheconnectionrelationshipandattributerecordsaresimple,thedisadvantageisthattherouteisoftenbackandforth,repeated.

按路线采集的优点是路线基本不往返、重复，效率高，缺点是草图连接关系和属性记录容易混淆。Whencollectingaccordingtotheroute,theadvantageisthattherouterarelygoesbackandforthandrepeated,theefficiencyishigh,thedisadvantageisthattheconnectionrelationshipandattributerecordsonthesketchareeasytoconfuse.碎部点采集路线规划PlanningofCollectionRouteforFragmentPoints在碎部点采集实施过程中，地物点与地貌点二者经常会重叠。因此，合理选择碎部点位置，也会提高数据采集效率。Intheimplementationoffragmentarypointcollection,terrainpointsandtopographypointsoftenoverlap.Therefore,choosingreasonablefragmentarypointpositionscanalsoimprovetheefficiencyofdatacollection.碎部点采集路线规划PlanningofCollectionRouteforFragmentPoints在碎部点采集过程中，由于采集设备通视要求或者卫星信号接收的要求，我们经常在地物点采集时会选择构筑物的顶部作为采集对象，这时其采集获得的高程点就不能在内业成图时参与等高线的绘制，否则会导致地形失真。Inthefielddatacollectionprocess,duetothevisibility